The present invention relates to elevator systems and, more particularly, to a belt guide system to provide tracking for flexible, flat elevator ropes.
Flexible, flat elevator ropes are used in certain elevator systems because they provide several advantages over conventional, round ropes such as high traction and low profile. Flat elevator ropes have certain drawbacks, however, including a tendency to have poor tracking during operation. If a flat rope does not track properly, noise is generated by the a misaligned rope that is objectionable to passengers. Under severe misalignment conditions, the edges of the flat rope are susceptible to damage and may require premature replacement.
It is an object of the present invention to provide a flat rope guide device for elevator systems that provides improved rope tracking and minimizes or prohibits misalignment.
It is a further object of the present invention to provide a rope guide device that minimizes or removes excessive noise or wear on flat ropes in elevator systems.
It is a further object of the present invention to provide a rope guide device for elevator systems that makes the flexible, flat rope more forgiving to sheave misalignment and rope twist associated with particular hoistway and elevator system configurations.
These and other objects are achieved by the present invention described herein.
One embodiment of the present invention is directed to an elevator guide system for rope tracking. Although the present invention may be implemented for use with various types of elevator ropes including round ropes, the preferred embodiments are described with respect to flat ropes. In addition, it should be noted that the present invention may be utilized with either traction sheaves or with idler sheaves, and may be mounted on the car, the counterweight, or the machine in a position proximate to the sheaves. The linear guidance system prevents the flat rope from hitting the shoulders on a rotating sheave, and thereby prevent the rope from prematurely degrading or emitting objectionable sounds. The system is integrated into the car and counterweight sheave in such a way as to be easily adjustable and serviceable.
The elevator rope guide system according to the present invention comprises one or more guide block bodies having one or more channels generally aligned with sheave grooves to which each block is adjacently positioned using a frame-mount. The guide blocks align the flat belt on entry into and exit from a sheave.
A second preferred embodiment is directed to the use of one or more guide roller assemblies, instead of guide blocks, wherein each roller assembly has one or more channels, each formed by a rotatable ring-shaped members mounted for rotation about an axle. A set of flanges may be used to separate each roller, each thereby forming a wall or shoulder.
It should be noted that through the implementation of either embodiment it is possible to use a sheave in combination with the present invention wherein the sheave has no need for grooves or shoulders formed by flanges to guide the belt around the sheave. One advantage of such a system is that the wear on a belt or belt jacket normally associated with such flanges or shoulders is eliminated.